ALLEN PARK, Mich. — It was only fitting for the Lions’ game at historic Wembley Stadium in London to come down to a kick, but what happened in the first 59:56 was as much of an emotional rollercoaster as the final field goal.

Matt Prater hit a 48-yarder as time expired to give the Lions a 22-21 victory over the Atlanta Falcons, capping a 21-point comeback that gives them two wild victories before heading to the bye.

But the Lions were just as close to losing the game as Prater missed a 43-yarder on what would’ve been the final play if not for a delay-of-game penalty against the Lions. The Falcons began to celebrate and many Lions thought the game was over, too.

“That’s about as high and as low and as high again as I’ve been on a football field,” quarterback Matthew Stafford said.

Now, the Lions are 6-2 and atop the NFC North thanks to what has been a charmed season to this point, particularly by a defense that allowed just 80 yards in the second half Sunday.

In the first half, the game seemed over as the Falcons scored on their first two drives and had a 21-0 lead at halftime. In the second half, the Lions steadily mounted their comeback, but the feeling after some missed opportunities resembled Stafford’s initial thoughts on the critical delay-of-game call, which he said was the best such penalty “in the history of the world.”

“I thought it was a 10-second runoff. I didn’t know. I was like, awesome,” he said.

Instead of the clock running out, the Lions had one last chance, and Prater’s kick ensured the stellar second-half performances by Stafford, Golden Tate, Theo Riddick and the entire defense weren’t for naught.

“You should never miss twice in a row,” Prater said.

With Calvin Johnson, Reggie Bush and their top three tight ends sidelined — not to mention the ease with which the Falcons’ offense operated — the 21-0 lead seemed insurmountable.

But the Lions’ defense returned to form in the second half, including an interception by cornerback Cassius Vaughn and two sacks, and the offense finally started to move the ball after gaining just 103 yards in the first half.

Stafford was 24-for-47 for 325 yards, two touchdowns and an interception. Tate had seven catches for 151 yards and a touchdown and Riddick caught eight passes for 74 yards and a touchdown.

“The name of the game in this business is wins — scoring points and winning,” Stafford said. “And this team believes in each other, no matter who’s out there, who’s not out there, and that’s fun to be around.”

NOTES: DT Nick Fairley reportedly suffered a sprained MCL and PCL in his right knee and could miss only a month rather than the rest of the season. … With nine catches, WR Golden Tate joined Herman Moore as the only players in franchise history with 50 catches in the first eight games of a season. Tate had seven catches for 151 yards and a touchdown. He already has four 100-yard games this season, more than he had in four seasons with the Seattle Seahawks (three). … Caldwell declined to provide an explanation for DT C.J. Mosley’s two-week suspension, which the team announced Saturday. “Violation of team rules,” he said. “That’s about all I want to go into with that one.” He’ll be available for Week 10 against the Miami Dolphins.

REPORT CARD VS. FALCONS

–PASSING OFFENSE: C-plus — As with most of the units, the passing offense was a tale of two halves Sunday. In the first half, Matthew Stafford finished 9 of 20 for 85 yards and an interception, but in the second half, he was 15 of 27 for 240 yards and two touchdowns. Golden Tate had seven catches for 151 yards and a touchdown, and running back Theo Riddick caught eight passes for 74 yards and a touchdown.

–RUSHING OFFENSE: D — Even though the Lions were playing from behind and had to pass, they showed an almost embarrassing lack of confidence in the running game against a team that hasn’t stopped anyone in recent weeks. Joique Bell led the Lions with 14 carries for 39 yards as the Lions finished with just 60 yards on 23 carries.

–PASS DEFENSE: B — Matt Ryan carved up the Lions easily in the first half, with two touchdowns and three long scoring drives. But in the second half, the secondary played lights out, highlighted by Cassius Vaughn’s interception on a horrendous pass by Ryan to nobody in particular. Plus, the Lions had two sacks in the second half after creating no pressure in the first.

–RUSH DEFENSE: B-minus — Steven Jackson had success early, including a second-quarter touchdown run, but the Lions limited him to 60 yards on 18 carries. Overall, the Falcons had just 78 yards on 26 carries, but that’s a surprisingly bad game for the Lions considering the mismatch in the trenches.

–SPECIAL TEAMS: A-minus — It didn’t matter what else happened because Matt Prater making all three field-goal attempts was the special-teams highlight of the season so far. Sam Martin deserves credit for minimizing Devin Hester on kickoffs and punts.

–COACHING: D — Jim Caldwell’s clock management nearly cost the Lions the game Sunday as he appeared to be settling for about a 50-yard field goal, calling a run play on third down at the Atlanta 30 with just 24 seconds left. Lucky for Caldwell, Atlanta’s defense had a holding penalty on the play, and Mike Smith’s clock management was even worse.